Key-responding selector mechanism

ABSTRACT

The construction of mechanical devices having a multiple of elements to be actuated selectively in varying combinations is enhanced by use of a shiftable selector plate which can be punched from sheet stock and/or molded accurately and inexpensively. The selector plate has a movable rectangular selecting section integrally connected to two colinear guiding sections by means of three flexible bar sections arranged one between each section. The guiding sections have individual intermediately located pivot bores dividing the sections in like proportions. Pivot pins in the pivot bores restrain the guiding sections to pivotal movement about the bores. This restrains the movement of the other section to a line absolutely perpendicular to the line defined by the pivot pins in the pivot bores. Each of the selecting sections of the selector plates has a multiple of substantially square apertures in registry with corresponding apertures in all of the other plates. Keys are extended through the apertures in all of the selector plates in registry. The keys in the plates have surfaces cooperating with edges of the apertures of the plates defining the forward direction of the plates of two different characteristics distributed in predetermined permutation for all of the keys. Depressing a key shifts the selector plates relative to one another in accordance with the distribution of the two different characteristics. The guiding sections of the plates are pivoted at central points so that the selecting sections move directly forward regardless of the location of the particular key which is actuating the plates. The leading edge of the selector plates for the particular character desired may bear directly against the ends of the blade elements remote from the printing ends, or linking elements can be interposed between the printing blade elements and the selector plates. The square apertures of the plates which are to remain at rest for the selection of a given character are enlarged so that depressing the associated key will not disturb them. A camming element preferably is arranged in the apertures between the actuating surface of the keys and the actuating surfaces of the selector plates to provide more uniform motion.

United States Patent [72] Inventors Reynold Benjamin Johnson Palo Alto; I Edward Everett Long; George Edmund Price, San Jose, Calif.

[21] Appl. No. 829,652

[22] Filed June 2, 1969 [45] Patented Mar. 2, 1971 [73] Assignee International Business Machines Corporation Armonk, N.Y.

{5X1 Kev nEsroNmNc SELECTOR MECHANISM 8 Claims, 4 Drawing Figs.

Primary Examiner-RobertE. Pulfrey Assistant Examiner-C. Coughenour Attorneyl-lanifin & .lancin ABSTRACT: The construction of mechanical devices having a multiple of elements to be actuated selectively in varying combinations is enhanced by use of a shiftable selector plate which can be punched from sheet stock and/or molded accurately and inexpensively. The selector plate has a movable rectangular selecting section integrally connected to two colinear guiding sections by means of three flexible bar sections arranged one between each section. The guiding sections have individual intermediately located pivot bores dividing the sections in like proportions. Pivot pins in the pivot bores restrain the guiding sections to pivotal movement about the bores. This restrains the movement of the other section to a line absolutely perpendicular to the line defined by the pivot pins in the pivot bores. Each of the selecting, sections of the selector plates has a multiple of substantially square apertures in registry with corresponding apertures in all of the other plates. Keys are extended through the apertures in all of the selector plates in registry. The keys in the plates have surfaces cooperating with edges of the apertures of the plates defining the forward direction of the plates of two different characteristics distributed in predetermined permutation for all of the keys. Depressing a key shifts the selector plates relative to one another in accordance with the distribution of the two different characteristics. The guiding sections of the plates are pivoted at central points so that the selecting sections move directly forward regardless of the location of the particular key which is actuating the plates. The leading edge of the selector plates for the particular character desired may bear directly against the ends of the blade elements remote from the printing ends, or linking elements can be interposed 1 between the printing blade elements and the selector plates.

The square apertures of the plates which are to remain at restfor the selection of a given character are enlarged so that depressing the associated key will not disturb them. A camming element preferably is arranged in the apertures between the actuating surface of the keys and the actuating surfaces of the selector plates to provide more uniform motion.

PATENTED m 219?:

1) mil b I N VEN TORS REY LD B. JOHNSON ED D E. LONG GEORGE E.PRICE ATTORNEY KEY-RESPONDING SELECTOR MECHANISM This application is related to copending U.S. Pat. application Ser. No. 829,653 filed on Jun. 2, 1969, of Paul Anthony Gilovich, Reynold Benjamin Johnson, Edward Everett Long, David Harwood McMurtry, Ernest George Nassimbene, Thomas Frank ORourke and George Edmund Price for Mechanical Type Printing Apparatus, and Ser. No. 829,642 filed on the same day, of Reynold Benjamin Johnson and Ralph Engene Marrs for a Mechanical Power Transmission System.

The invention relates to an accurately shiftable actuator plate mechanism and it particularly pertains to such mechanismsfor mechanical key responsive type printing apparatus but it is not limited thereto.

In the contemporary alphameric character printing art, attention is being directed to simplified, low-cost, manually operated type printing apparatus for use in conjunction with data processing systems such as commercial billing systems, and the like, and computer-assisted instructional systems. Such apparatus is in need of low cost but accurately controllable coding mechanisms. 1 i

Conventional wire printing apparatus, printing telegraph apparatus, and various forms of typewriting apparatus have used rods, notched bars, and apertured plates of expensive construction and critical dimensions for this purpose. Examples of this prior art are to be found in the following U.S. Pat. Nos.: 2,851,141, Sept. 1958, Kistner, 197-1; 2,943,150, Jun. l960,llandley, 178-30; 3,276,560, Oct. 1966,Wirtz, 197-18; 3,324,985, Jun. 1967, Palmer, et al., l97-16; and 3,334,720, Aug. 1967, Hickerson, 197-49.

According to the invention, theobjects indirectly referred to hereinbefore and those which will appear hereinafter are attained in key responsive selector plates of integral construction having a movable selecting section and two guiding sections. The guiding sections are arranged in end-to-end relationship and linked to each other by a flexible bar section and to the movable section by two further flexible bar sections. Each of the guiding sections has a pivot point intermediate the ends dividing the guiding section in like proportions. In operation, the movable section is urged along a line normal to the line defined by the pivot points in the guiding sections. The guiding sections are restrained to pivotal motion about the pivot points. This restraint further restrains the motion of the movable section so that a line or an edge of the movable section parallel to the pivot point line can move only precisely parallel to the pivot point line.

In a machine having aplurality of elements to be moved, such as the wires in a wire printer, the elements are shifted in 1 response to a plurality of selector plates in a stack. The selector plates are moved relative to one another by means of keys arranged in apertures in registry in the stack of selector plates. The keys in the plates have cooperative surfaces at edges of the plates defining at least parts of the apertures of two different characteristics distributed in predetermined permutation, one for each aperture and key combination, enabling the shifting of said selector plates relative to one another in accordance with the distribution of the two different characteristics. In one embodiment, the different characteristics are located in the keys and in another embodiment the different characteristics are in the apertures in the selector plates. In

the latter embodiment, the forward edge of the selector plates which are to remain in the rest position are cut away so that depression of the key does not effect any movement of these plates. Preferably, a camming element is located in the aper- FIG. 1 is an isometric view of a partial assembly of apparatus using a shiftable selector plate according to the invention;

FIG. 2 is a plan view of a shiftable selector plate according to the invention illustrating the principle of operation;

FIG. 3 is an end view of a stack of selector plates according to the invention; and

FIG. 4,. sections a and b being taken together illustrates means for reducing frictiorr effects between plates in a large stack.

An example of an application of the shiftable selector plate according to the invention is shown in FIG. 1. A printing head 24, which may be that of conventional wire printer apparatus or a sort of apparatus according to the copending U.S. Pat. ap-

ing elements of the head 24 are moved forward toward a platen member 135 and against the record medium 140 in response to the shifting of selector plates 60 according to the invention which are stacked atop the spacing plate 58. Keys 70, only a few of which are. shown, are arranged to shift one or more selector plates 60 and the spacing plate 58 in printing the characters corresponding to the keys 70. It is essential that the leading edge 88 of the selector plates 60 and the spacing selector plate 58 move forward precisely the same distance in all positions of the carrier 45 across the record 140 for uniform printing despite any tendency for any key (particularly one to either side of the center) to cant one or more plates. Each displaceable plate 60 as shown in FIGS. 1 and 2 comprises a moveable selecting section 81, two guiding sections 82 and 83 joined together by a flexible bar section 84 and joined at the other ends to the selecting section 81 by two further flexible bar sections 85 and 86. Four pins 90 are mounted in line across the frame 54 of the machine, as shown in FIG. 1, and the plates are arranged on the frame with the pins 90 protruding through apertures 9'1, 92 and 93. Thepins 90 and apertures 9l93 are of dimensions permitting the guiding sections 82 and 83 to pivot about the pins in apertures 92 and 93 and to so pivot without restraintwith respect to the pins in the larger apertures 91. The plates are made of relatively thin material of such resilience that the flexible bar sections restrain the leading edge 94 in the forward movement to a line absolutely parallel to the line defined by the pins 90 despite any tendency to cant due to offcenter pressure from a key depression. Many materials are suitable for the plates. For example, one embodiment used cotton base phenolic l/32- inch thick (0.031) and others used tempered aluminum of thicknesses of 0.012 and 0.015 inch. These plates were produced by punching. Molded plates of suitable materials such as polyethylene terephthalate, better known by the re gistered trademark Mylar (R)," of approximately 0.013-inch thickness are contemplated. Less expensive plates may be made of steel of 0.007-inch stock. These plates afford long life in that the flexible bar sections are less prone to fatigue but are inherently heavyand thus, there is high inertia to be overcome in moving the steel plates. In embodiments of the invention, the selector plates have been arranged to move distances of 0.125 inches to 0.050 inches although less and greater distances can be accommodated depending upon the circumstances.

In embodiments where the plates are stacked one upon another, two distinctly different though similar plates are used. The difference lies in staggering the location of the flexible bar sections 84, and 86 as better shown in the end view of a stack of five plates in FIG. 3. This staggering eliminates any possibility of the edges 'of the flexible bar sections and adjacent edges of the plates from snagging on each other especially with respect to the crosswise component of motion undergone in the flexing of these portions ofthe plates. In the interests of clarity, only five selector plates are shown in FIG. 3, but it should be understood that any practical number of plates may be used according to the invention.

Where a large number of plates are stacked one atop the other, there is a ceiling to the frictional loading at which the selection of one or two plates near the bottom may carry another unselected plate along. FIG. 4 shows a structure eliminating this possibility. Again, only four selector plates 58, 60, 61 and 62 are shown for simplicity, but it should be understood that the arrangement is more and more advantageous as the number of plates is increased. Each plate is supported by amultiple of rockers arranged for limited movement in apertures in a base spring plate 55 fixed in the frame 54 and resting on a rocker support 57. Three or four rockers for each plate will be found satisfactory, though only one rocker for a plate is shown in the interest of simplicity. For example, the spacing selector plate 58 is supported by three or more rockers 58R. The plates 58, 60 and 61 have apertures permitting the rockers 60R 61R to pass through for supporting the plate above. Friction between rockers is reduced by means of bosses 59 located at suitable points.

The keys 70 move the selector plates by pressure on the forward edges of the apertures 96 in which the keys are arranged. Those plates which are not to be moved have the apertures enlarged at least in the forward direction so that the plate is undisturbed by movement of the key 70 in the larger aperture. The leading edge 88 of selector plates according to the invention also can be moved forward by corresponding movement of the guiding sections 82 and 83. An aperture 98 similar to the key apertures 96 is located in the longer guiding section 82 on the center line of the selector plate 60. Conveniently, the stem of a space bar which is similar in construction to the stems of the keys 70, is arranged in the apertures 98 of all of the plates in the stack. The apertures 98 in the selector plates 60 are made sufficiently large and of such configuration that none of the character selector plates 60 are disturbed by depression of the space bar. The aperture 98 in the spacing selector plate 58 is arranged to cam the guiding section 82 rearward in pivotal motion about the pin 90 in the aperture 92. The edge of the aperture 98 in the spacing plate 58 remote from the leading edge 88 is parallel to the leading edge 88 when the guiding section 82 is in its rearmost position. The other edges of the aperture 98 in the spacing selector plate 58 are relieved so that the space bar stem does not bind as the guiding section 82 pivots. The apertures 96 and 98 may be circular for those plates to be moved by the depression of a key having cylindrical form and elongated into oval shape or those plates not to be moved by the particular key arranged therein. Preferably, the apertures 96 and 98 are substantially rectangular in form as shown permitting the use of a pressure equalizing cam member in conjunction with each of the keys 70 and with the space bar key stern 110.

In alternate embodiments, the selector plates, according to the invention, have all of the apertures 96 of uniform size and the keys arranged in those apertures have notches in the stems for effecting the selection. When a key is depressed, the corresponding plates ntove into the notches, under spring pressure for example, and other plates are restrained by the absence ofa notch ofa key stem. ln such an arrangement, the plates must be spaced from each other so that in the uppermost position of all the keys, the plates are restrained and allowed to move only when a notch appears in the depressed condition of a key. In these embodiments staggering is unnecessary so that only a single model of selector plate is required for a line of machines. This is highly advantageous as molding a large number of different key stems (for example, 88 in a large keyboard) is less expensive than punching a smaller number (for example 13) of different plates and interchangeable keys can be utilized with the character for which each key is notched molded into the key top.

Also, the different plates 6062 can cause the closing of electric circuit contacts thus encoding the key operation into any desirable code, for example, a binary code. The parallel movement of the plates 6062 is equally desirable for closing and opening electric circuit contacts as for printing, especially where close timing is of the essence.

While the invention has been shown and described particularly with reference to a preferred embodiment thereof, and various alternative structures have been suggested, it should be clearly understood that those skilled in the art may effect further changes without departing from the spirit and scope of the invention.

We claim: 1, A shiftable plate of integral construction having a movable section with one edge to be moved in a direction normal thereto, and two guiding sections arranged in end-to-end relationship joined together by a flexible bar section and joined at the opposite ends to said movable section by two further flexible bar sections normally substantially parallel to the first said flexible bar sections, said guiding sections having pivot points located in a line parallel to said one edge and dividing the sections in like proportions, whereby restraining said guiding sections to rotational movement about said pivot points thereby restrains movement of said one edge of said movable section parallel to said line of said pivot points.

2. A key responding selector mechanism, comprising: a frame; at least one key movably mounted on said frame; at least one selector plate arranged on said frame and having a selecting section in working relationship with said key to be moved in a given direction with respect to said frame in response to movement ofsaid key;

two guiding sections arranged in end-to-end relationship joined together by a flexible bar section extending in said given direction and joined at the opposite ends to said selecting section by two further flexible bar sections normally substantially parallel to the first said flexible bar sections, said guiding sections each having an aperture intermediate the ends thereof dividing the sections in like proportions; and

a pair of pins fixed to said frame in a line normal to said given direction, and passing through said apertures restraining said guiding sections to rotational movement about the pins; thereby restraining movement of said selecting section to the line of said given direction.

3. A key-responding selector mechanism, comprising:

a frame;

a plurality of selector plates stacked on said frame;

each of said selector plates having a selecting section with a multiple of apertures therein and one edge to be moved selectively in a given direction with respect to said frame, in response to movement of one of said keys;

two guiding sections arranged in end-to-end relationship joined together by a flexible bar section and joined at the opposite ends to said selecting section by two further flexible bar sections normally substantially parallel to the first said flexible bar sections;

said guiding sections having bores intermediate the ends thereofdividing the sections in like proportions;

a multiple of keys movably mounted on said frame and protruding through said apertures;

said keys and said apertures having complementary configurations of two differing characteristics for selective apertures of said selecting sections;

at least one pair of pins fixed to said frame in a line parallel to said one edge and passing through said bores for restraining said guiding sections to rotational movement about the pins, and thereby restraining movement of said one edge of said selecting section to the wherein of said given direction.

4. A key responding selector mechanism as defined in claim 3 and wherein said apertures are of two differing dimensions in said given direction in each selector plate, and the differing apertures are permutated in a predetermined coding for selective operation of said plates.

5. A key responding selector mechanism as defined in claim 4 and wherein said guiding sections are of equal length, and said bores are centered lengthwise in said guiding sections 6. A key-responding selector mechanism as defined in claim 4 and wherein said guiding sections are of differing lengths 7 and wherein the layer of said guiding sections of each plate has an aperture on said center line for a key and said guiding section apertures of the stack of plates are of differing dimensions for selectively operating said plates with movement in a direction opposite to said given direction, thereby to actuate the selecting section of the selected plates in said given direction. 

1. A shiftable plate of integral construction having a movable section with one edge to be moved in a direction normal thereto, and two guiding sections arranged in end-to-end relationship joined together by a flexible bar section and joined at the opposite ends to said movable section by two further flexible bar sections normally substantially parallel to the first said flexible bar sections, said guiding sections having pivot points located in a line parallel to said one edge and dividing the sections in like proportions, whereby restraining said guiding sections to rotational movement about said pivot points thereby restrains movement of said one edge of said movable section parallel to said line of said pivot points.
 2. A key responding selector mechanism, comprising: a frame; at least one key movably mounted on said frame; at least one selector plate arranged on said frame and having a selecting section in working relationship with said key to be moved in a given direction with respect to said frame in response to movement of said key; two guiding sections arranged in end-to-end relationship joined together by a flexible bar section extending in said given direction and joined at the opposite ends to said selecting section by two further flexible bar sections normally substantially parallel to the first said flexible bar sections, said guiding sections each having an aperture intermediate the ends thereof dividing the sections in like proportions; and a pair of pins fixed to said frame in a line normal to said given direction, and passing through said apertures restraining said guiding sections to rotational movement about the pins; thereby restraining movement of said selecting section to the line of said given direction.
 3. A key-responding selector mechanism, comprising: a frame; a plurality of selector plates stacked on said frame; each of said selector plates having a selecting section with a multiple of apertures therein and one edge to be moved selectively in a given direction with respect to said frame, in response to movement of one of said keys; two guiding sections arranged in end-to-end relationship joined together by a flexible bar section and joined at the opposite ends to said selecting section by two further flexible bar sections normally substantially parallel to the first said flexible bar sections; said guiding sections having bores intermediate the ends thereof dividing the sections in like proportions; a multiple of keys movably mounted on said frame and protruding through said apertures; said keys and said apertures having complementary configurations of two differing characteristics for selective apertures of said selecting sections; at least one pair of pins fixed to said frame in a line parallel to said one edge and passing through said bores for restraining said guiding sections to rotational movement about the pins, and thereby restraining movement of said one edge of said selecting section to the wherein of said given direction.
 4. A key responding selector mechanism as defined in claim 3 and wherein said apertures are of two differing dimensions in said given direction in each selector plate, and the differing apertures are permutated in a predetermined coding for selective operation of said plates.
 5. A key responding selector mechanism as defined in claim 4 and wherein said guiding sections are of equal length, and said bores are centered lengthwise in said guiding sections.
 6. A key-responding selector mechanism as defined in claim 4 and wherein said guiding sections are of differing lengths and have two bores each with one bore sufficiently large to permit rotation of the guiding section about the other bore.
 7. A key-responding selector mechanism as defined in claim 6 aNd wherein said flexible bar sections are offset with respect to the center line of said selector plates in said given direction, and alternate plates are offset to opposite sides of said centerline, thereby to prevent binding of adjacent plates in the stack of plates.
 8. A key responding selector mechanism as defined in claim 7 and wherein the layer of said guiding sections of each plate has an aperture on said center line for a key and said guiding section apertures of the stack of plates are of differing dimensions for selectively operating said plates with movement in a direction opposite to said given direction, thereby to actuate the selecting section of the selected plates in said given direction. 